In the manufacture of semiconductor wafers and semiconductor devices, regarding manufacturing apparatuses therefor, to prevent the processed products being contaminated with various types of soiling, attach ed substances, and so on, or to carry out vapor deposition processes, hermetically sealed chambers are primarily used, and an apparatus constitution in which a plurality of such chambers are arranged connected together is widely used.
Moreover, in such manufacture, housing means called a wafer carrier is used for conveying wafers and transferring the wafers between apparatuses, or a handling apparatus or the like for holding the wafers one at a time is used. Such a wafer carrier has a constitution in which a large number of semiconductor wafers are held in a line by means of a large number of grooves provided in an inside surface of the wafer carrier, and minute silicon dust is liable to be generated.
Every time it is required to increase the degree of integration of semiconductor devices, it is required to reduce the amount of attached matter on semiconductor wafers, and hence there is an increase in the required degree of cleanliness in the various process apparatuses and so on. Consequently, minute silicon dust, and also oil films and so on caused by oily components or the like that have leaked out from a pump or the like of any of various manufacturing apparatuses installed in a clean room or sebum generated from workers in the clean room, which are difficult to remove, are the most loathed contaminants.
In the case of cleaning a series of device manufacturing apparatuses that have been set up using a cleaning liquid containing, for example, a surfactant for removing oily components and so on, another way of cleaning is required to remove the surfactant and so on, and hence contamination occurs in chain-like fashion; in general, a cleaning liquid that does not contain a surfactant is thus used, and hence it is extremely difficult to remove the above-mentioned oil films and so on.
Moreover, as insertion of silicon wafers into and carrying out of silicon wafers from the various apparatuses is continuously carried out, it is impossible to avoid extremely minute silicon dust becoming attached inside the apparatuses; the surface of this dust is oxidized over time, whereby a tough oxide film is produced.
Furthermore, wafer carriers of which the inside and outside surfaces have become soiled through repeated use are periodically cleaned since this soiling will cause contamination of the semiconductor wafers themselves. Up until now the cleaning of wafer carriers has been carried out through automatic cleaning using a high-pressure jet, Megasonic cleaner or the like, or hand brush cleaning using an organic solvent. However, it has not been easy to remove extremely minute silicon pieces that have become stuck in a carrier.